RESUMO
A complete quantum cooling cycle may be a useful platform for studying quantum thermodynamics just as the quantum heat engine does. Entropy change is an important feature which can help us to investigate the thermodynamic properties of the single ion cooling process. Here, we analyze the entropy change of the ion and laser field in the single ion cooling cycle by generalizing the idea in Reference (Phys. Rev. Lett. 2015, 114, 043002) to a single ion system. Thermodynamic properties of the single ion cooling process are discussed and it is shown that the Second and Third Laws of Thermodynamics are still strictly held in the quantum cooling process. Our results suggest that quantum cooling cycles are also candidates for the investigation on quantum thermodynamics besides quantum heat engines.
RESUMO
We propose a ground state cooling scheme for an optomechanical resonator based on the system of one Λ-type three-level atom trapped in an optomechanical cavity. This cooling scheme works in a single-photon coupling, and strong atom-cavity coupling regimes. By investigating the cooling dynamics, we find that there is an EIT-like quantum coherent effect in this system which can suppress the undesired transitions for heating. Moreover, our study shows that the final average phonon number of the optomechanical resonator can be smaller than the one based on the sideband cooling. Furthermore, the ground state cooling of the resonator can still be achieved after thermal fluctuations included. In addition, in comparison with previous cooling methods, there are fewer limitations on the decay rates of both the cavity and the atom in this scheme. As a result, this scheme is very suitable to realize the ground cooling of an optomechanical resonator in the experiment.
Assuntos
Sistemas Microeletromecânicos/instrumentação , Fótons , Campos Eletromagnéticos , Desenho de EquipamentoRESUMO
Three-dimensional (3D) imaging of individual atoms is a critical tool for discovering new physical phenomena and developing new technologies in microscopic systems. However, the current single-atom-resolved 3D imaging methods are limited to static circumstances or a shallow detection range. Here, we demonstrate a generic dynamic 3D imaging method to track the extensive motion of single ions by exploiting the engineered point-spread function (PSF). We show that the image of a single ion can be engineered into a helical PSF, thus enabling single-snapshot acquisition of the position information of the ion in the trap. A preliminary application of this technique is demonstrated by recording the 3D motion trajectory of a single trapped ion and reconstructing the 3D dynamical configuration transition between the zig and zag structures of a 5-ion crystal. This work opens the path for studies on single-atom-resolved dynamics in both trapped-ion and neutral-atom systems.
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AIMS: Previous studies have indicated that IFI30 plays a protective role in human cancers. However, its potential roles in regulating glioma development are not fully understood. METHODS: Public datasets, immunohistochemistry, and western blotting (WB) were used to evaluate the expression of IFI30 in glioma. The potential functions and mechanisms of IFI30 were examined by public dataset analysis; quantitative real-time PCR; WB; limiting dilution analysis; xenograft tumor assays; CCK-8, colony formation, wound healing, and transwell assays; and immunofluorescence microscopy and flow cytometry. RESULTS: IFI30 was significantly upregulated in glioma tissues and cell lines compared with corresponding controls, and the expression level of IFI30 was positively associated with tumor grade. Functionally, both in vivo and in vitro evidence showed that IFI30 regulated the migration and invasion of glioma cells. Mechanistically, we found that IFI30 dramatically promoted the epithelial-mesenchymal transition (EMT)-like process by activating the EGFR/AKT/GSK3ß/ß-catenin pathway. In addition, IFI30 regulated the chemoresistance of glioma cells to temozolomide directly via the expression of the transcription factor Slug, a key regulator of the EMT-like process. CONCLUSION: The present study suggests that IFI30 is a regulator of the EMT-like phenotype and acts not only as a prognostic marker but also as a potential therapeutic target for temozolomide-resistant glioma.
Assuntos
Glioma , beta Catenina , Humanos , beta Catenina/genética , beta Catenina/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferon gama/metabolismo , Transição Epitelial-Mesenquimal , Temozolomida/farmacologia , Temozolomida/uso terapêutico , Glicogênio Sintase Quinase 3 beta , Resistencia a Medicamentos Antineoplásicos , Linhagem Celular Tumoral , Movimento Celular , Glioma/genética , Fenótipo , Receptores ErbB/metabolismo , Proliferação de Células , Regulação Neoplásica da Expressão GênicaRESUMO
PRMT6, a type I arginine methyltransferase, di-methylates the arginine residues of both histones and non-histones asymmetrically. Increasing evidence indicates that PRMT6 plays a tumor mediator involved in human malignancies. Here, we aim to uncover the essential role and underlying mechanisms of PRMT6 in promoting glioblastoma (GBM) proliferation. Investigation of PRMT6 expression in glioma tissues demonstrated that PRMT6 is overexpressed, and elevated expression of PRMT6 is negatively correlated with poor prognosis in glioma/GBM patients. Silencing PRMT6 inhibited GBM cell proliferation and induced cell cycle arrest at the G0/G1 phase, while overexpressing PRMT6 had opposite results. Further, we found that PRMT6 attenuates the protein stability of CDKN1B by promoting its degradation. Subsequent mechanistic investigations showed that PRMT6 maintains the transcription of CDC20 by activating histone methylation mark (H3R2me2a), and CDC20 interacts with and destabilizes CDKN1B. Rescue experimental results confirmed that PRMT6 promotes the ubiquitinated degradation of CDKN1B and cell proliferation via CDC20. We also verified that the PRMT6 inhibitor (EPZ020411) could attenuate the proliferative effect of GBM cells. Our findings illustrate that PRMT6, an epigenetic mediator, promotes CDC20 transcription via H3R2me2a to mediate the degradation of CDKN1B to facilitate GBM progression. Targeting PRMT6-CDC20-CDKN1B axis might be a promising therapeutic strategy for GBM.
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Glioblastoma , Proteínas Nucleares , Humanos , Proteínas Nucleares/metabolismo , Glioblastoma/genética , Histonas/genética , Histonas/metabolismo , Proteínas de Ciclo Celular/metabolismo , Metilação , Proteína-Arginina N-Metiltransferases/genética , Proteína-Arginina N-Metiltransferases/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Proteínas Cdc20/genética , Proteínas Cdc20/metabolismoRESUMO
The treatment of lumbar spinal synovial cysts (LSCs) which are relatively rare but can cause neurogenic dysfunction and intractable pain has been a controversial topic for many years. Surgical excision of LSCs is the standard treatment for patients in whom conservative treatment options fail. This meta-analysis was undertaken to compare clinical outcomes between minimally invasive approaches using tubular retractors (microscopic vs. endoscopic) and traditional percutaneous approaches for LSCs. Studies reporting surgical management of LSCs were searched in the Cochrane Library, PubMed and Web of Science database. This meta-analysis was reported following the PRISMA Statement, registered in Prospero (CRD42021288992). A total of 1833 patients were included from both the related relevant studies (41 studies, n = 1831) and the present series (n = 2). Meta-analysis of minimally invasive tubular approaches revealed no statistically significant difference in pain improvement, dural tear, residual cyst, recurrence and operation time between minimal groups with traditional groups (p > 0.05). Minimal groups had better Functional improvement of 100% (95% CI 1.00-1.00; p < 0.001, I2 = 75.3%) and less reoperation rates of 0% (95% CI - 0.00-0.00; p = 0.007, I2 = 47.1%). Postoperative length of hospital stay and intraoperative bleeding in minimal groups were also less than traditional groups (p < 0.05). Subgroup analysis revealed endoscopic groups had less operation time (p = 0.004), and there was no significant difference in the rest. For patients with LSCs but without obvious clinical and imaging evidence of vertebral instability, even when preoperative stable grade 1 spondylolisthesis is present, minimally invasive tubular approaches without fusion may provide the best outcome in surgical management.
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Fusão Vertebral , Espondilolistese , Cisto Sinovial , Humanos , Resultado do Tratamento , Vértebras Lombares/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Espondilolistese/cirurgia , Cisto Sinovial/cirurgia , Fusão Vertebral/métodosRESUMO
BACKGROUND: SPRY4-IT1 (SPRY4 intronic transcript 1) is a long non-coding RNA (lncRNA) that has been identified as a novel oncogene in various cancers, including glioma. However, its function and underlying mechanism in glioma remain largely unclear. Here, we investigated the role of SPRY4-IT1 in the development of glioma and its underlying mechanism. METHODS: Bioinformatics analysis and RT-qPCR assay were used to examine the expression of SPRY4-IT1 in glioma tissues. The CCK-8, EdU, and Xenograft tumor assays wereperformed to assess the proliferation effect of glioma cells. The tube forming assay and Chick Embryo Chorioallantoic Membrane (CAM) assay were conducted to detect the angiogenesis effect of HUVECs. RNA-sequencing, western blotting, RT-qPCR, ELISA, and IHC assays were employed to verify the regulatory mechanism of the SPRY4-IT1/ miR-101-3p/EZH2/VEGFA axis. RESULTS: Analysis of the TCGA dataset and data from our own cohort demonstrated that SPRY4-IT1 was overexpressed in patients with glioma, and high SPRY4-IT1 expression correlated with poor prognosis. In vitro and in vivo experiments showed that SPRY4-IT1 promoted the proliferation of glioma cells. RNA sequencing and Gene Ontology (GO) enrichment analysis indicated significant enrichment of angiogenesis. HUVEC tube forming assay and CAM assay confirmed that SPRY4-IT1 could induce angiogenesis of glioma cells in vitro and in vivo. Mechanistically, SPRY4-IT1 upregulated EZH2 expression by sponging miR-101-3p to induce VEGFA expression in glioma cells. Moreover, SPRY4-IT1 activated the VEGFR2/AKT/ERK1/2 pathway in HUVECs mediated by glioma cells. Rescue experiments further confirmed that SPRY4-IT1 promoted glioma cell proliferation and angiogenesis via the miR-101-3p/EZH2/VEGFA signaling axis. CONCLUSIONS: Our findings provide compelling evidence showing that SPRY4-IT1 upregulated EZH2 to induce VEGFA by sponging miR-101-3p, thereby achieving cell proliferation and angiogenesis in glioma. Therefore, targeting SPRY4-IT1/miR-101-3p/EZH2/VEGFA axis may improve the outcomes of patients with glioma.
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Glioma , MicroRNAs , RNA Longo não Codificante , Embrião de Galinha , Animais , Humanos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Linhagem Celular Tumoral , Glioma/genética , Proliferação de Células/genética , MicroRNAs/genética , Regulação Neoplásica da Expressão Gênica , Movimento Celular/genética , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismoRESUMO
Nuclear transcription factor Mesenchyme Homeobox 2 (MEOX2) is a homeobox gene that is originally discovered to suppress the growth of vascular smooth muscle and endothelial cells. However, whether or not it is connected to cancer is yet unknown. Here, we report that MEOX2 functions as a tumor-initiating element in glioma. Bioinformatic analyses of public databases and investigation of MEOX2 expression in patients with glioma demonstrated that MEOX2 was abundant at both mRNA and protein levels in glioma. MEOX2 expression was shown to be inversely linked with the prognosis of glioma patients. MEOX2 inhibition changed the morphology of glioma cells, inhibited cell proliferation and motility, whereas had no effect on cell apoptosis. Besides, silencing MEOX2 also hampered the epithelial-mesenchymal transition (EMT), focal adhesion formation, and F-actin assembly. Overexpression of MEOX2 exhibited opposite effects. Importantly, RNA-sequencing, ChIP-qPCR assay, and luciferase reporter assay revealed Cathepsin S (CTSS) as a novel transcriptional target of MEOX2 in glioma cells. Consistently, MEOX2 causes glioma tumor development in mice and greatly lowers the survival period of tumor-bearing mice. Our findings indicate that MEOX2 promotes tumorigenesis and progression of glioma partially through the regulation of CTSS. Targeting MEOX2-CTSS axis might be a promising alternative for the treatment of glioma.